The effect of initial longitudinal velocity of the first tunneling electron on the nonsequential double-ionization (NSDI) process is studied using a semiclassical model. Our analysis shows that nonzero initial longitu...
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The effect of initial longitudinal velocity of the first tunneling electron on the nonsequential double-ionization (NSDI) process is studied using a semiclassical model. Our analysis shows that nonzero initial longitudinal velocity affects two distinct typical trajectories [single-return collision (SRC) and multiple-return collision (MRC)] in the NSDI process in different ways: for SRC, the yield in the center part of the correlation momentum distribution is reduced; for MRC, the tunneling time of the first electron is apparently delayed. In comparison with the case of zero initial longitudinal velocity, the double ionization is suppressed for a long wavelength, and a better agreement with the experimentally observed electron correlation distribution is achieved when the nonzero initial longitudinal velocity is taken into account.
We theoretically investigate high-order harmonic generation and attosecond pulses by numerically solving the three-dimensional time-dependent Schrödinger equation from a helium ion in a two-color laser field, whi...
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We theoretically investigate high-order harmonic generation and attosecond pulses by numerically solving the three-dimensional time-dependent Schrödinger equation from a helium ion in a two-color laser field, which is synthesized by adding a 1600-nm laser pulse to a multicycle 800-nm laser pulse. The numerical results show that the short quantum path selection and broadband continuum spectra are achieved by adjusting the relative phase between two laser pulses, and isolated attosecond pulses can be generated successfully. Compared with the case of He+ ions from the 1s ground state, the emission efficiency of the continuous harmonics and the intensity of the isolated attosecond pulse are enhanced approximately thirteen orders of magnitude by preparing He+ ions in a coherent superposition of the states 1s and 2s. Furthermore, the bandwidth of the continuum spectrum is further broadened by increasing the intensity of the 1600-nm laser pulse, and an intense 38-as isolated pulse with a bandwidth of 109 eV is straightforwardly obtained.
The position-momentum Shannon and Rényi uncertainty products of general quantum systems are shown to be bounded not only from below (through the known uncertainty relations), but also from above in terms of the H...
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The position-momentum Shannon and Rényi uncertainty products of general quantum systems are shown to be bounded not only from below (through the known uncertainty relations), but also from above in terms of the Heisenberg-Kennard product 〈r2〉〈p2〉. Moreover, the Cramér-Rao, Fisher-Shannon, and López-Ruiz, Mancini, and Calbet shape measures of complexity (whose lower bounds have been recently found) are also bounded from above. The improvement of these bounds for systems subject to spherically symmetric potentials is also explicitly given. Finally, applications to hydrogenic and oscillator-like systems are done.
In this paper, we present the structure and the dynamics of highly charged heavy ions studied through dielectronic recombination (DR) observations performed with the Tokyo electron beam ion trap. By measuring the ener...
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Reliable experimental demonstrations of violations of local realism are highly desirable for fundamental tests of quantum mechanics. One can quantify the violation witnessed by an experiment in terms of a statistical ...
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Reliable experimental demonstrations of violations of local realism are highly desirable for fundamental tests of quantum mechanics. One can quantify the violation witnessed by an experiment in terms of a statistical p value, which can be defined as the maximum probability according to local realism of a violation at least as high as that witnessed. Thus, high violation corresponds to small p value. We propose a prediction-based-ratio (PBR) analysis protocol whose p values are valid even if the prepared quantum state varies arbitrarily and local realistic models can depend on previous measurement settings and outcomes. It is therefore not subject to the memory loophole [J. Barrett et al., Phys. Rev. A 66, 042111 (2002)]. If the prepared state does not vary in time, the p values are asymptotically optimal. For comparison, we consider protocols derived from the number of standard deviations of violation of a Bell inequality and from martingale theory [R. Gill, e-print arXiv:quant-ph/0110137]. We find that the p values of the former can be too small and are therefore not statistically valid, while those derived from the latter are suboptimal. PBR p values do not require a predetermined Bell inequality and can be used to compare results from different tests of local realism independent of experimental details.
In this paper we present a comprehensive analysis of line tension-driven compositional interface fluctuations in planar lipid bilayer membranes. Our starting point is the advective Cahn-Hilliard equation for the local...
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In this paper we present a comprehensive analysis of line tension-driven compositional interface fluctuations in planar lipid bilayer membranes. Our starting point is the advective Cahn-Hilliard equation for the local lipid composition in symmetric membranes, which explicitly incorporates both advective and diffusive lipid transport processes, and which is coupled to the continuum hydrodynamic equations governing the flow behavior of the membrane and surrounding solvent with finite subphase thickness. In order to extract the interface dynamics from the continuum phase-field formalism, we first derive the appropriate sharp-interface limit equations. We then carry out a linear perturbation analysis for the relaxational dynamics of small-amplitude sinusoidal interface fluctuations to yield the general dispersion relation ωk as a function of perturbation wave number k. The resulting expression incorporates the effects of diffusive and advective lipid transport processes within the membrane, viscous or viscoelastic membrane properties, coupling between membrane and solvent, and inertial effects within the membrane and solvent. It is shown that previously considered scenarios naturally emerge as limiting cases of the general result. Furthermore, we discuss two additional scenarios amenable to analysis, one in which the inertia of the solvent is relevant, and another one in which the membrane displays significant viscoelastic properties. Finally, we numerically evaluate the general dispersion relation for three representative model membrane systems.
Perturbation theory predicts that a massless fermion cannot possess a measurable magnetic moment. We explain, however, that the nonperturbative phenomenon of dynamical chiral symmetry breaking generates a momentum-dep...
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Perturbation theory predicts that a massless fermion cannot possess a measurable magnetic moment. We explain, however, that the nonperturbative phenomenon of dynamical chiral symmetry breaking generates a momentum-dependent anomalous chromomagnetic moment for dressed light quarks, which is large at infrared momenta, and demonstrate that consequently these same quarks also possess an anomalous electromagnetic moment with similar magnitude and opposite sign.
In many scientific and engineering problems the solidification of an alloy leads to a highly convoluted crystalline matrix modeled as a thermodynamically controlled reactive porous medium called a mushy layer. We anal...
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In this paper, we review various LTPS backplane technologies based on laser-crystallization and other related methods that have been applied to AMLCD and AMOLED displays. The TFT performances obtained by different mel...
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We present a physically intuitive model of ice-lens formation and growth during the freezing of soils and other dense, particulate suspensions. Motivated by experimental evidence, we consider the growth of an ice-fill...
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We present a physically intuitive model of ice-lens formation and growth during the freezing of soils and other dense, particulate suspensions. Motivated by experimental evidence, we consider the growth of an ice-filled crack in a freezing soil. At low temperatures, ice in the crack exerts large pressures on the crack walls that will eventually cause the crack to split open. We show that the crack will then propagate across the soil to form a new lens. The process is controlled by two factors: the cohesion of the soil and the geometrical supercooling of the water in the soil, a new concept introduced to measure the energy available to form a new ice lens. When the supercooling exceeds a critical amount (proportional to the cohesive strength of the soil) a new ice lens forms. This condition for ice-lens formation and growth does not appeal to any ad hoc, empirical assumptions, and explains how periodic ice lenses can form with or without the presence of a frozen fringe. The proposed mechanism is in good agreement with experiments, in particular explaining ice-lens pattern formation and surges in heave rate associated with the growth of new lenses. Importantly for systems with no frozen fringe, ice-lens formation and frost heave can be predicted given only the unfrozen properties of the soil. We use our theory to estimate ice-lens growth temperatures obtaining quantitative agreement with the limited experimental data that are currently available. Finally we suggest experiments that might be performed in order to verify this theory in more detail. The theory is generalizable to complex natural-soil scenarios and should therefore be useful in the prediction of macroscopic frost-heave rates.
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